Still, Twitter is a very toxic place, now more than ever. So it's beyond to me why someone wanting to be "unreachable" still uses it - or any kind of social media, that is.
If I were that famous, had the resources and wanted to be "unreachable", I'd follow the Donald Knuth way - just an email that is managed by his secretary who would filter it and let me know just the absolutely important stuff.
I think one would use Twitter not for being 'reachable', but for the broadcasting/promotion side of it. Social media is still incredibly useful for that, and Twitter especially.
As for the 1 hour a day - he does say it's not -just- sex. It is not unreasonable to spend an hour a day cuddling/hugging/whatever with your partner, while, say, watching a TV show. That would count.
If I were that famous, had the resources and wanted to be "unreachable", I'd follow the Donald Knuth way - just an email that is managed by his secretary who would filter it and let me know just the absolutely important stuff.
(Note aside, 1 hour a day for sex!?)